I have the hp equivalencies of the electric outboards to reasonably accurate when it comes to using for sailboat auxiliary. On my 19ft Mariner, most use 4-6hp gas outboards, which push them to hull speed and then some, dragging big wakes. The 3hp outboards don't quite reach hull speed, but are fine otherwise. And the 1-2hp outboards are used by the racers to get out to the course, and then removed from the motor mount.
In my case, I chose a 3hp equivalent Epropulsion Spirit. However, battery usage is a lot more dependent on boat speed (throttle) than gasoline usage on a gas outboard. My range varies from 12nm at 4kts to 18nm at 2kts. And range drops to less than 6nm at 5.5kts. This takes some getting used to - don't go as fast as you can. I've shot the 4kt currents in the Niantic River (Long Island Sound) just fine.
If you would be satisfied with a 5hp gas outboard, the Torqueedo XP will do just fine. Just realize slowing down preserves battery and increases range. And with the quiet of the electric, slowing down to "smell the roses" is quite enjoyable. I motor more with the electric than I did with the gas outboard.
just my experiences
Fred W
Stuart Mariner 19 #4133 Sweet P
